Teaching your children how to save money at an early age is a great thing. They would learn how to value money and what factors does it contribute to an everyday living. We have piggy banks at home that my Burritos used to stash coins. When we go to the store and they "want" to buy something, I always ask them "Do you really need it?" Then if they say that they don't the amount of the money that they want to spend gets to go to their piggy bank when we comes home.
At the end of the year, they count their coins, their cash gifts received, and the money they earned for our rewards system at home and decide whether they put it in the bank or buy a big thing they want. It always ended depositing it in their savings bank, their "Adult Money".
Last year, they accumulated over $200 each so that was added to their savings account. This practice not only teaches kids how to save and value money but they also apply their Mathematics skills at home.